[FIX] Livechat build without NodeJS installed (#15903)

packages/rocketchat-livechat/plugin/build.sh

@@ -18,6 +18,6 @@ cd $LIVECHAT_DIR
 cp -a $ROOT/node_modules/\@rocket.chat/livechat/build/. ./
 # change to lowercase so all injected junk from rocket.chat is not sent: https://github.com/meteorhacks/meteor-inject-initial/blob/master/lib/inject-core.js#L10
 # this is not harmful since doctype is case-insesitive: https://www.w3.org/TR/html5/syntax.html#the-doctype
-node -e 'fs.writeFileSync("index.html", fs.readFileSync("index.html").toString().replace("<!DOCTYPE", "<!doctype"));'
+meteor node -e 'fs.writeFileSync("index.html", fs.readFileSync("index.html").toString().replace("<!DOCTYPE", "<!doctype"));'
 cd $ROOT/$LIVECHAT_ASSETS_DIR
 cp ../../public/livechat/index.html .